The Euro 6 Real-Driving Emissions (RDE) procedure for light-duty vehicles: Effectiveness and practical aspects

摘要

The European Union has adopted a real-driving emissions (RDE) test procedure to complement the standard laboratory test for the type-approval of light-duty vehicles. The RDE procedure defines requirements for the design and execution of trips on the road and contains evaluation methods to verify the normality of driving conditions. This article assesses the practicality and effectiveness of RDE provisions with respect to operating conditions, in particular trip composition and dynamicity. To this end, we test three vehicles on a total of 8 different routes across Europe. The analysis indicates that (i) the requirements regarding trip dynamicity and (ii) the coverage of normal driving conditions as implemented by the moving averaging window method do effectively contain the variability of on-road driving and, at the same time, ensure practicality of the RDE procedure. Out of 10 purposefully designed trips, four are invalidated by the RDE requirements: one each due to excessive stop time during urban driving and an insufficient coverage of urban driving, respectively, and two due to excessive or insufficient dynamicity. Our results suggest that the overall trip verification process consists of largely complementary rather than redundant steps. Although subject to limitations, our assessment suggests that the RDE boundary conditions and evaluation methods are practical, effective, and do not unduly obstruct emissions testing of light-duty vehicles on the road.